/**
 * Copyright 2019 吉鼎科技.

 * <p>
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package cn.easyplatform.org.objectweb.asm;

/**
 * An {@link FieldVisitor} that generates Java fields in bytecode form.
 * 
 * @author Eric Bruneton
 */
final class FieldWriter implements FieldVisitor {

	/**
	 * Next field writer (see {@link ClassWriter#firstField firstField}).
	 */
	FieldWriter next;

	/**
	 * The class writer to which this field must be added.
	 */
	private final ClassWriter cw;

	/**
	 * Access flags of this field.
	 */
	private final int access;

	/**
	 * The index of the constant pool item that contains the name of this
	 * method.
	 */
	private final int name;

	/**
	 * The index of the constant pool item that contains the descriptor of this
	 * field.
	 */
	private final int desc;

	/**
	 * The index of the constant pool item that contains the signature of this
	 * field.
	 */
	private int signature;

	/**
	 * The index of the constant pool item that contains the constant value of
	 * this field.
	 */
	private int value;

	// /**
	// * The runtime visible annotations of this field. May be <tt>null</tt>.
	// */
	// private AnnotationWriter anns;
	//
	// /**
	// * The runtime invisible annotations of this field. May be <tt>null</tt>.
	// */
	// private AnnotationWriter ianns;

	/**
	 * The non standard attributes of this field. May be <tt>null</tt>.
	 */
	private Attribute attrs;

	// ------------------------------------------------------------------------
	// Constructor
	// ------------------------------------------------------------------------

	/**
	 * Constructs a new {@link FieldWriter}.
	 * 
	 * @param cw
	 *            the class writer to which this field must be added.
	 * @param access
	 *            the field's access flags (see {@link Opcodes}).
	 * @param name
	 *            the field's name.
	 * @param desc
	 *            the field's descriptor (see {@link Type}).
	 * @param signature
	 *            the field's signature. May be <tt>null</tt>.
	 * @param value
	 *            the field's constant value. May be <tt>null</tt>.
	 */
	FieldWriter(final ClassWriter cw, final int access, final String name,
			final String desc, final String signature, final Object value) {
		if (cw.firstField == null) {
			cw.firstField = this;
		} else {
			cw.lastField.next = this;
		}
		cw.lastField = this;
		this.cw = cw;
		this.access = access;
		this.name = cw.newUTF8(name);
		this.desc = cw.newUTF8(desc);
		if (ClassReader.SIGNATURES && signature != null) {
			this.signature = cw.newUTF8(signature);
		}
		if (value != null) {
			this.value = cw.newConstItem(value).index;
		}
	}

	// ------------------------------------------------------------------------
	// Implementation of the FieldVisitor interface
	// ------------------------------------------------------------------------

	// public AnnotationVisitor visitAnnotation(
	// final String desc,
	// final boolean visible)
	// {
	// if (!ClassReader.ANNOTATIONS) {
	// return null;
	// }
	// ByteVector bv = new ByteVector();
	// // write type, and reserve space for values count
	// bv.putShort(cw.newUTF8(desc)).putShort(0);
	// AnnotationWriter aw = new AnnotationWriter(cw, true, bv, bv, 2);
	// if (visible) {
	// aw.next = anns;
	// anns = aw;
	// } else {
	// aw.next = ianns;
	// ianns = aw;
	// }
	// return aw;
	// }

	public void visitAttribute(final Attribute attr) {
		attr.next = attrs;
		attrs = attr;
	}

	public void visitEnd() {
	}

	// ------------------------------------------------------------------------
	// Utility methods
	// ------------------------------------------------------------------------

	/**
	 * Returns the size of this field.
	 * 
	 * @return the size of this field.
	 */
	int getSize() {
		int size = 8;
		if (value != 0) {
			cw.newUTF8("ConstantValue");
			size += 8;
		}
		if ((access & Opcodes.ACC_SYNTHETIC) != 0
				&& ((cw.version & 0xFFFF) < Opcodes.V1_5 || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0)) {
			cw.newUTF8("Synthetic");
			size += 6;
		}
		if ((access & Opcodes.ACC_DEPRECATED) != 0) {
			cw.newUTF8("Deprecated");
			size += 6;
		}
		if (ClassReader.SIGNATURES && signature != 0) {
			cw.newUTF8("Signature");
			size += 8;
		}
		// if (ClassReader.ANNOTATIONS && anns != null) {
		// cw.newUTF8("RuntimeVisibleAnnotations");
		// size += 8 + anns.getSize();
		// }
		// if (ClassReader.ANNOTATIONS && ianns != null) {
		// cw.newUTF8("RuntimeInvisibleAnnotations");
		// size += 8 + ianns.getSize();
		// }
		if (attrs != null) {
			size += attrs.getSize(cw, null, 0, -1, -1);
		}
		return size;
	}

	/**
	 * Puts the content of this field into the given byte vector.
	 * 
	 * @param out
	 *            where the content of this field must be put.
	 */
	void put(final ByteVector out) {
		int mask = Opcodes.ACC_DEPRECATED
				| ClassWriter.ACC_SYNTHETIC_ATTRIBUTE
				| ((access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) / (ClassWriter.ACC_SYNTHETIC_ATTRIBUTE / Opcodes.ACC_SYNTHETIC));
		out.putShort(access & ~mask).putShort(name).putShort(desc);
		int attributeCount = 0;
		if (value != 0) {
			++attributeCount;
		}
		if ((access & Opcodes.ACC_SYNTHETIC) != 0
				&& ((cw.version & 0xFFFF) < Opcodes.V1_5 || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0)) {
			++attributeCount;
		}
		if ((access & Opcodes.ACC_DEPRECATED) != 0) {
			++attributeCount;
		}
		if (ClassReader.SIGNATURES && signature != 0) {
			++attributeCount;
		}
		// if (ClassReader.ANNOTATIONS && anns != null) {
		// ++attributeCount;
		// }
		// if (ClassReader.ANNOTATIONS && ianns != null) {
		// ++attributeCount;
		// }
		if (attrs != null) {
			attributeCount += attrs.getCount();
		}
		out.putShort(attributeCount);
		if (value != 0) {
			out.putShort(cw.newUTF8("ConstantValue"));
			out.putInt(2).putShort(value);
		}
		if ((access & Opcodes.ACC_SYNTHETIC) != 0
				&& ((cw.version & 0xFFFF) < Opcodes.V1_5 || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0)) {
			out.putShort(cw.newUTF8("Synthetic")).putInt(0);
		}
		if ((access & Opcodes.ACC_DEPRECATED) != 0) {
			out.putShort(cw.newUTF8("Deprecated")).putInt(0);
		}
		if (ClassReader.SIGNATURES && signature != 0) {
			out.putShort(cw.newUTF8("Signature"));
			out.putInt(2).putShort(signature);
		}
		// if (ClassReader.ANNOTATIONS && anns != null) {
		// out.putShort(cw.newUTF8("RuntimeVisibleAnnotations"));
		// anns.put(out);
		// }
		// if (ClassReader.ANNOTATIONS && ianns != null) {
		// out.putShort(cw.newUTF8("RuntimeInvisibleAnnotations"));
		// ianns.put(out);
		// }
		if (attrs != null) {
			attrs.put(cw, null, 0, -1, -1, out);
		}
	}
}
